Customarily electro reduction furnaces are provided with tapholes in the area of the bottom which are closed by means of a taphole gun which presses an appropriate plastic medium into the taphole. For tapping, the opening is bored or burned open. The closing and in particular the opening of the taphole demands a certain amount of time since, first of all, the tap gun or boring machine has to be positioned in working position. Furthermore it necessitates that there be space corresponding to the movement of the machines within the proximity of the tapholes.
It is a known fact that pouring ladles are to be provided with a discharge outlet. In connection with known model types, this is a stable plate which is associated with the ladle, which plate has an opening to which is fastened a second plate which may be moved which also has a corresponding opening, may be slid away. When the container is to be emptied the openings in the plates are aligned with each other; when the movable plate is slid aside, the opening is closed. With this model type it is necessary, that the plates lie close together so that no liquidmetal may enter between them and interfere with the tightness of the closure. For all that, this may not always be avoidable. Even an installation which presses the movable plate against the stable one does not result in any material improvement.
It is the aim of the invention to improve an electro-metal smelting furnace of the above-mentioned type in such a way that the tapping of the metal smelt may be carried out faster and with fewer problems. This aim is achieved according to the invention through application of the characteristics in the claims.
As practice has demonstrated, the tapping periods are materially shortened through the use of a simple closure developed like a type of shutter. Since the plate which closes the taphole is swung away from the pouring spray when opening there is no abrasion. The counter surface against which the shutter rests when in closure position may be fittingly developed in such a way that it stays free from the metal which pours through the hole. It is appropriate after tapping and prior to processing the new smelt to fill the pipe-shaped taphole which passes through the furnace lining, with a pourable material, for instance sand, which under the effect of the heat from the smelt cakes together and prevents the metal from directly affecting the closure shutter. This material may be chosen with a view to fracturing when opening the closure shutter and thereby releasing the taphole.
An example of an embodiment of the invention is shown in the drawing:
It shows: